1. Field of the Invention
The present invention relates to a sheet discharge mechanism used in printers, facsimile machines or the like. In particular, the present invention relates to a sheet discharge mechanism provided with electrically conductive brush capable of removing electrostatic charge generated at discharge rollers. The present invention also relates to apparatus incorporating such a sheet discharge mechanism.
2. Description of the Related Art
Conventionally, sheet discharge mechanisms are incorporated in various apparatus, such as printers, facsimile machines or the like for purposes of discharging sheet members (such as recording paper sheets) out of the apparatus. To this end, a typical sheet discharge mechanism may include a rotary shaft driven by a suitable actuator such as a stepping motor, and discharge rollers fixedly mounted around the shaft. In operation, a sheet member to be discharged is held in contact with the discharge rollers. In this state, while the discharge rollers are rotated, the sheet member is moved in a predetermined discharging direction due to friction between the sheet member and the discharge rollers.
In a normal situation, the sheet member will eventually come out of contact with the discharge rollers, and then fall into a discharged sheet tray of the apparatus for example.
A problem associated with the conventional sheet discharge mechanism is as follows. In operation, the sheet member and the discharge rollers may be electrostatically charged due to the friction between the sheet member and the discharge rollers. In such a case, the rear end portion of the sheet member may unduly be kept attached to the discharge rollers even when the rear portion is supposed to leave the discharge rollers. If this happens, the sheet member tends to be unfavorably transferred backward or even wound around the discharge rollers.
One of the possible ways to address the above problem may be to provide an electrically conductive brush in the apparatus in a manner such that the brush comes into direct contact with a charged sheet member. However, it has been found that such a brush cannot completely remove the electrostatic charge from the sheet member. Thus, the improper sheet transfer described above may still result in the conventional sheet discharge mechanism.